Drop IE support from Sass

scss/forms/_form-select.scss

@@ -37,7 +37,7 @@
       // For visual consistency with other platforms/browsers,
       // suppress the default white text on blue background highlight given to
       // the selected option text when the (still closed) <select> receives focus
-      // in IE and (under certain conditions) Edge.
+      // in Edge.
       // See https://github.com/twbs/bootstrap/issues/19398.
       color: $input-color;
       background-color: $input-bg;